FRIDAY, May 21 (HealthDay News) -- What do creative people and people diagnosed with schizophrenia have in common? According to new research out of Sweden, both share similar dopamine systems in the brain.

Dopamine, along with serotonin, is a key neurotransmitter - chemicals that are vital to transmitting messages via nerve cells in the brain.

"We have studied the brain and the dopamine D2 receptors, and have shown that the dopamine system of healthy, highly creative people is similar to that found in people with schizophrenia," Fredrik Ullen, associate professor at Karolinska Institute's department of women's and children's health in Stockholm, said in a news release.

Ullen and his team gleaned their finding, which was published online May 17 in PLoS One, from work with schizophrenia patients and healthy individuals who were deemed creative after completing psychological testing that focused on problem-solving.

"The study shows that highly creative people who did well on the divergent tests had a lower density of D2 receptors in the thalamus than less-creative people," Ullen said. "Schizophrenics are also known to have low D2 density in this part of the brain, suggesting a cause of the link between mental illness and creativity."

The thalamus region of the brain, the authors noted, is a kind of filter for information before it moves on to the cortex region, which handles understanding and reasoning.

The researchers pointed out that people with highly creative skills have previously been shown to also have a higher likelihood of having mental illness in their family. Creativity itself has also been associated with a modestly higher risk for both bipolar disorder and schizophrenia.

Both groups also share a talent for drawing unusual, sometimes bizarre links between thoughts and concepts.

Creative people, therefore, might benefit from having fewer D2 receptors because a reduced amount of filtering would translate into a higher flow of information, the study team speculated. In turn, this might explain why creative individuals tend to come upon less obvious solutions to problems and, for similar reasons, why the mentally handicapped might also tend to reach "outside the box" in favor of relatively novel associations.

Nevertheless, Ullen and his colleagues stated that they are not yet clear on which specific brain mechanisms are at the heart of this apparent association.